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Phonon-phason coupling in icosahedral quasicrystals

W. -J. Zhu·C. L. Henley
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Abstract

From relaxation simulations of decoration-based quasicrystal structure models using microscopically based interatomic pair potentials, we have calculated the (usually neglected) phonon-phason coupling constant. Its sign is opposite for the two alloys studied, i-AlMn and i-(Al,Cu)Li; a dimensionless measure of its magnitude relative to the phonon and phason elastic constants is of order 1/10, suggesting its effects are small but detectable. We also give a criterion for when phonon-phason effects are noticeable in diffuse tails of Bragg peaks.

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W. -J. Zhu, C. L. Henley. 1998-12-09. Phonon-phason coupling in icosahedral quasicrystals. https://doi.org/10.1209/epl%2Fi1999-00328-9

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